i see so many of these regular vs premium gas threads. In my area price difference between the two is 30cents per gallon, so with a full tank fill-up you're saving what...$4, $5? really? c'mon now.

my coworker got mad at me when i told him he should've gotten a civic instead of new Benz if his concern was saving $5 a week with cheaper no-name gas. I don't get some people's logic...

Exactly! And that's only if your running the tank to near dry too. It's really not that big of a difference, the better argument would be milage relative to tank capacity. That could be a bigger difference.

Regardless, you loose performance and won't get the listed MPG if you run regular, so that alone can be the difference of the $4 or $5 extra you spend to fill up premium.

Just sold my 04 GS and got a 13 GS. In the 04, I always always used premium gas because the gas cap said to use only premium gas. The salesman at the dealership that I bought the new 2013 car from said that I can use the cheap stuff in the new one and nothing bad will happen.

Has anyone gone crazy and tried the lower octane gas? If so, did anything bad happen?

Usually you would get lower gas mileage when not using premium. I do not think anything would happen immediately when using a lower grade but long term it might. There are tons of Premium vs mid/regular threads. Just read them and make a decision. Me personally the price difference is not that much plus lost in mileage makes it a no brainier. Just put the recommended premium and enjoy your new car.

Just remember this. You have 6 large injectors and 6 smaller ones. The ECU controls gas flow through both sets at various times. Looking at the fuel system, its complexity and the cost of the components. I personally wouldn't run cheap stuff on a regular basis.

Can you run lower octane gas in your 13 GS that "requires" premium... (of course!)

What will happen? You will get worse gas mileage and less performance numbers from your car. There are knock sensors in most new cars of today that will recognize lower octane gas and take care of any issues related to quicker detonation that used to lead to engine knock when lower octane gas was used. This is no longer the case...so no worries there.

Is it worth it? Let's see depending on where you live...you're talking an extra $5 for a full fill up. You purchased a performance luxury car at around $60k...is $5 worth it to you???

A vehicle which travels 15,000 miles a year, which consumes an average of 20 miles per gallon, would use 750 gallons in one year. If higher octane fuel costs roughly $0.40 more per gallon it would cost an additional $300 a year to use that fuel in that vehicle. $300, which is $25 a month, represents approximately 0.5% of the price of a $55,000 vehicle.

When I first purchased the gs i started using only premium fuel then the prices of gas rased to 4+ a gallon then I started using regualr 87 gas in the car and have been using it since. I have noticed no change in gas mileage, nor performance. I'm sure there is a diffrence between 93 and 87 as far as performance but I havent noticed it.

When I first purchased the gs i started using only premium fuel then the prices of gas rased to 4+ a gallon then I started using regualr 87 gas in the car and have been using it since. I have noticed no change in gas mileage, nor performance. I'm sure there is a diffrence between 93 and 87 as far as performance but I havent noticed it.

You can use regular as long as you don't stomp on it.That's where the difference comes in.89 would be a better choice,IMO.
Many that lease will use 87.

In my opinion, if you're not putting the suggested premium gas in the car..why get a 50K+ car? Sounds a little like you're "living outside of your means" if you're worried about the extra $25-$50 more a month on gas.